>> dna tests confirmed this blood was brenda's. but bevel also found mist-like blood spatter on brenda's jeans below the knee, which had penetrated deep into the fabric. >> it is from a high-velocity occurrence, such as a gunshot, in this case, multiple gunshot pellets that has spattered the blood traveling back from him, referred to as back spatter, and then subsequently, landing on her clothing. >> dna tests confirmed that this was rob's blood. this proved that brenda was standing only a few feet away from rob when he was killed. >> the back spatter on the pants, i think that gave us that one bit of evidence we needed in order to put that gun in ms. andrew's hand. >> prosecutors believe brenda planned her husband's murder for months.